US Bridges

SULLIVAN-S280 Onrp over S280-S1 Connector Ramp

Fair

San Mateo County, California · 04-SM-280-R25.34-DLC · Structure no. 35 0186K

Built
1967
58 years old
Condition
Fair
inspected February 2025
Type
Box Beam or Girders - Multiple
Concrete Continuous
Length
335 ft
3 main spans
Daily traffic
8,600
2002 count
Owner
State
State Highway Agency

About this bridge

SULLIVAN-S280 Onrp over S280-S1 Connector Ramp is a concrete continuous box beam or girders - multiple carrying SULLIVAN-S280 Onrp over S280-S1 Connector Ramp in San Mateo County, California. It was built in 1967, so it is 58 years old, older than the California average of 54.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 8,600 vehicles a day, roughly 2% of them trucks, projected to reach 28,142 by 2047. The structure is 335 ft (102 m) long and 28 ft wide.

Location

Open in Google Maps
CarriesSULLIVAN-S280 Onrp
CrossesS280-S1 Connector Ramp
Location04-SM-280-R25.34-DLC
RouteInterstate 280
CountySan Mateo County
StateCalifornia
Coordinates37.67836, -122.47199
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Last inspectionFebruary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating66.5 US tons
Inventory rating40 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length335 ft (102 m)
Longest span141 ft (43.1 m)
Deck width28 ft (8.4 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic8,600 (2002)
Projected traffic28,142 by 2047
Trucks2%
Lanes on structure1
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was SULLIVAN-S280 Onrp over S280-S1 Connector Ramp built?

It was built in 1967, making it 58 years old in 2025.

What condition is SULLIVAN-S280 Onrp over S280-S1 Connector Ramp in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in February 2025.

How much traffic does SULLIVAN-S280 Onrp over S280-S1 Connector Ramp carry?

About 8,600 vehicles per day (2002 count), of which roughly 2% are trucks.

How long is SULLIVAN-S280 Onrp over S280-S1 Connector Ramp?

The structure is 335 ft (102 m) long with a longest span of 141 ft (43.1 m) and a deck 28 ft wide.

Who owns SULLIVAN-S280 Onrp over S280-S1 Connector Ramp?

It is owned by the State Highway Agency.